The correct setting for avast mail scanner should be:
- on advanced page unclick the checkbox "The server requires a secure connection (SSL)" for smtp
- set the SMTP server port to 25
- do the same for POP, uncheck the checkbox and set the POP server port to 110.
The accounts seem to be properly configured in avast, together with their SSL setting, so this should be enough for the connection from your PC to the Mail server to be encrypted and protected by SSL, while at the same time readable to avast, so that it can scan it.